Data has been collected on the development of smoking during the school years with the goals of: 1. Describing the developmental history of smoking through four stages, the pre-experimental, experimental, continuing use and heavy use, and relating this to use of alcohol and other drugs; 2. Identifying the population most at risk for becoming regular smokers; and 3. Designing and testing an intervention targeted at high risk youngsters in a longitudinal study. We have interviewed 380 randomly selected Milwaukee public school students in grades 2 through 10, and are currently interviewing an additional 700 students in grades 6 through 12. The interview elicits detailed information on learning to use substances (food, candy, alcohol, over-the-counter medication) to control distress during the pre-experimental period; the erosion of anti-smoking attitudes by exposure to smoke, etc.; the nature of the respondent's first several experiences with cigarettes, focussing particularly of his psychological and physiological reactions, and on his interpretation of these reactions. We also assess the social and psychological context in which experimentation with cigarettes takes place, the factors that encourage continued experimentation and the life stresses that may produce high levels of cigarette and drug use. The respondent's model of health and illness, his levels of self esteem, autonomy, and future orientation will also be related to cigarette and drug use. Interventions are being designed to target each of the stages and to reach children at high risk for cigarette and drug use.